Effectiveness of Switching: Conventionals to Atypicals Over the past several years, new, so-called "atypical," antipsychotic medications have become available to treat schizophrenia. Olanzapine and risperidone are the two most widely prescribed antipsychotics; together they account for over 40 percent of all antipsychotic prescriptions. Given their wide usage, we know surprisingly little about the effectiveness of these newer medications in routine practice settings. Despite a decade of availability of atypical antipsychotics, about 40 percent of the antipsychotic prescriptions filled in the United States today are still for conventional agents. Given that the atypical antipsychotics may be more effective than the conventional ones and have less burdensome side effects, should people who are relatively stable on the older medications but who are still symptomatic or troubled by medication side effects be switched to an atypical medication? What are the benefits and risks associated with such medication switches? A total of 300 consenting patients with schizophrenia from a large, diverse public mental health system, who are living in the community and taking conventional antipsychotic medications but who are still troubled by symptoms or medication side effects, will be randomly assigned to stay on their current conventional antipsychotic medication (N =100) or to switch to olanzapine (N =100) or risperidone (N=100). This design specifically controls for process of changing medications because one group continues on current treatment. The proposed study, therefore, will assess what incremental risks and benefits can be expected from switching from a conventional to a first-line atypical antipsychotic agent. All medications will be open label, and treatment will be by the study participants' routine providers. Study participants will be asked to stay in their assigned treatment condition for 6 months, after which time medication decisions will be up to the patient and the prescribing psychiatrist. Study participants will be interviewed with quantitative instruments at baseline and at follow-up intervals for 1 year to determine clinical course and the types of services used. The study will determine the incremental risks and benefits of switching from a conventional to the most commonly prescribed atypical antipsychotics, and the relative risks and benefits of switching to olanzapine versus switching to risperidone.